1. Field of the Invention
This invention relates to an apparatus for opening and closing doors, and particularly to a door opening and closing apparatus for a railway platform which can accommodate trains having entrances of varying positions widths.
2. Description of the Prior Art
It is proposed by the official gazette of Japanese Patent Publication Application No. 57-2537 to form, at a platform for railway vehicles, a partition including a wall on the side of the platform facing the track and sliding doors on a face of the wall. The opening position of the sliding doors is adjusted in response to an error in the stopping position of a railway vehicle stopped at the platform, in order to assure the safety of passengers or enhance the air conditioning efficiency of a building formed at the platform. This type of structure functions well when the type of railway vehicle is fixed.
However, with the sliding door apparatus for a railway platform as described above, when railway vehicles of many different types are employed, the sliding door cannot be opened in conformity with entrances which vary widely in position and dimension. This is impossible particularly where it is necessary to change the sliding directions of the sliding doors.
Partitions provided with doors which are formed on the side of a platform facing a track must necessarily be spaced a considerable distance apart, to minimize shaking caused by trains passing or advancing into the platform at high speeds. If there is a considerable distance between a railway vehicle and a door in this manner, however, a problem arises in that passengers getting on and off of the train are forced into the space between the railway vehicle and the partition door. This problem is particularly pronounced when the platform or railway vehicle is crowded, such as during rush-hour commuting times. To solve the problem, it is desirable to provide protective equipment between the railway vehicle and the partition door, but this is very complicated.